1. Field of the Invention
The present invention relates to a recording and/or reproducing apparatus such as a video tape recorder (VTR) and, more particularly, to a sliding mechanism for sliding a cassette chassis on which a tape cassette is set.
2. Description of the Related Art
In this kind of recording and/or reproducing apparatus, for the purpose of reducing its entire size, a slidable chassis on which a tape cassette is set is slidably supported on a main chassis provided with a rotary drum, so that the slidable chassis is moved toward and away from the main chassis.
FIG. 8 diagrammatically shows a conventional recording and/or reproducing apparatus, particularly an arrangement example of a slidable-chassis sliding mechanism and its associated constituent components. As shown in FIG. 8, a rotary drum 1 is rotatably supported on a main chassis 2, and a slidable chassis 5 is supported for sliding movement on the main chassis 2 within a predetermined stroke (refer to a double-headed arrow A). A slide arm 4 is turnably supported on the main chassis 2 by a pin 2d, and is connected to a cam gear 3 by a pin 4a which is engaged with a cam slot of the cam gear 3. The slide arm 4, which is driven to turn about the pin 2d in interlocking relationship to the cam gear 3, and the slidable chassis 5 are pin-connected by a connecting pin 4b through a slot 10 of a member affixed to the slidable chassis 5 by fittings 11, so that the slidable chassis 5 is slid by the rotation of the cam gear 3.
In the example shown in FIG. 8, the connecting pin 4b which connects the slide arm 4 and the slidable chassis 5 is engaged with a slot portion (or slot) 10 formed in the slidable chassis 5. In this case, the slot portion 10 consists of a separate constituent component which is positionally adjustably secured to the slidable chassis 5 by screws 11.
In the example shown in FIG. 9, a slot portion 10' with which the connecting pin 4b is engaged is provided on the slidable chassis 5 by outsert molding.
However, the conventional recording and/or reproducing apparatus has a number of problems. In the case of the example shown in FIG. 8, since the slot portion 10 need be prepared as a separate constituent component, not only does the number of constituent components increase but also the number of steps required for positioning and fixing the slot portion 10 increases. This leads to an increase in cost.
The structure shown in FIG. 9 involves the risk of producing a play between the main chassis 2 and the slidable chassis 5 at either end of the travel stroke of the slidable chassis 5 because of the presence of a positional tolerance of the connecting pin 4b due to permissible variations in the dimensions of constituent components. If a play occurs during recording or reproduction, a slack in tape will occur, so that a recording/reproduction failure may occur. If a play occurs during cassette unloading, a variation will occur in the standby position of a guide post, such as a tension arm, which performs a cam operation according to the position of the slidable chassis 5, as shown in FIG. 9. The guide post whose standby position has varied may come into contact with and give damage to the tape.